Masonry block constructions with polymeric coating

ABSTRACT

In the construction of a structural block wall the method includes the steps of erecting on a base a wall of mortarless structural blocks, applying to opposite faces of the wall a fibre reinforced polymeric coating and anchoring the wall to the base with the fibre reinforced coating. The resultant wall possesses a structural integrity wherein compressive loads are borne by the structure blocks and tensile loads are borne by the fibre reinforced skin extending over the surface of the wall and onto the base to anchor the wall to the base.

FIELD OF THE INVENTION

THIS INVENTION is concerned with improvements in masonry blockconstructions.

BACKGROUND OF THE INVENTION

The invention is concerned particularly although not exclusively withreinforced mortarless block constructions.

Hollow structural blocks such as masonry blocks have been successfullyemployed for many years in the construction of load bearing and non-loadbearing walls in commercial buildings, domestic dwellings and otherstructures such as retaining walls, fences and the like. As used herein,the expression “masonry” block is intended to embrace all manner ofstructural blocks.

Generally speaking, masonry block walls are constructed on reinforcedconcrete footings or a concrete floor slab as a base. Such walls includemortared joints.

Depending upon wind loadings for such block walls, rigidity is conferredby the formation of integral reinforced piers wherein starter barsextend into the hollow wall cavity at spaced intervals steel reinforcingbars are inserted into the wall cavities occupied by the starter barsand fluid concrete is then poured into the wall cavities occupied by thesteel reinforcing bars to form spaced, steel reinforced piers in thewall structure.

In cyclone rated-areas it is necessary to be able to structurally tie aroof structure through steel rods to the footings or floor slab on whichthe masonry walls are constructed.

While generally satisfactory for their intended purpose, such mortarjointed structural block wall constructions suffer a number of practicaldisadvantages.

Not only are these prior art block wall construction techniquesextremely labour intensive, a high level of skill is required in blocklaying with mortared joints. Skilled labour is expensive and frequentlydifficult to obtain when required.

The requirement for starter bars to be accurately located in asupporting base such as footings or a raft slab combined with pouredconcrete steel reinforced piers at required spaced intervals addssubstantially to both labour and material costs, particularly in cyclonerated areas where roof tie down means must be incorporated in the wall.

Although mortarless masonry blocks have been proposed to reduce thelevel of skilled labour required, these have not found favour inbuilding construction due to reduced structural integrity and increasedreinforcing costs as well as poor weather resistance of mortarlessjoints.

Where it is required to form integral piers, it is usually necessary tohire a concrete pumping vehicle to pump a concrete slurry into the wallcavities at spaced intervals to encapsulate the reinforcing bars. Thisis expensive and time consuming.

OBJECT OF THE INVENTION

It is an aim of the present invention to overcome or ameliorate at leastsome of the shortcomings associated with prior art structural block wallconstructions.

SUMMARY OF THE INVENTION

According to one aspect of the invention there is provided a method forconstruction of a structural block wall, said method comprising thesteps of:—

-   -   erecting on a base a wall of mortarless structural blocks; and    -   applying to opposite faces of said wall a fibre reinforced        polymeric coating.

Suitably, at least some of a base course of structural blocks areanchored to said base.

Preferably, said at least some of a base course of structural blocks areanchored to said base by a polymeric adhesive compound.

If required, the structural blocks may include one or more projectionsengageable, in use, with complementary one or more recesses in anadjacent structural block.

Preferably, said structural blocks include projections and complementaryrecesses on opposed faces.

Suitably, said blocks are self-aligning when stacked.

Most preferably said opposed faces comprise upper and lower faces.

The structural blocks may include one or more apertures extendingbetween said upper and lower faces.

Suitably said fibre reinforced polymeric coating extends over a portionof said base to form a bond between said wall and said base.

Preferably said fibre reinforced polymeric coating extends over portionsof said base on opposite sides of said walls.

The fibre reinforced polymeric coating may extend over a top surface ofsaid wall.

If required, mounting brackets may be secured to an upper course ofblocks in said wall to permit, in use, connection of a roof structure tosaid wall.

Suitably, said mounting brackets are secured to respective structuralblocks by a polymeric adhesive compound.

If required, reveal surfaces in wall openings may have applied thereto afibre reinforced polymeric coating.

Preferably, said fibre reinforced polymeric coating includes a layer offibreglass reinforcing material.

The layer of fibreglass material may comprise a sheet of woven ornon-woven fibreglass.

Suitably, said fibreglass reinforcing material is an alkaline resistantgrade.

Preferably, said fibre reinforced polymeric coating is formed byapplying a base coating of a liquid curable polymeric composition to awall surface, positioning on said base coating a layer of fibrereinforcing material, applying to an exposed surface of said layer offibre reinforcing material a further coating of a liquid curablepolymeric composition and allowing said liquid curable polymericcomposition to cure.

The liquid curable polymeric composition may be applied to a surface ofthe wall and/or the exposed surface of said layer of fibre reinforcingmaterial by any suitable means such as spraying, trowelling, squeegeeapplication or the like.

Suitably, said base coating is applied to a substantially even thicknessby means of guide projections extending from opposite normally exposedfaces of said structural blocks.

Preferably, said guide projections comprise spaced substantiallyparallel ribs serving, in use, to guide a screeding or trowelling deviceto apply said base coating to a substantially even thickness.

If required, a decorative coating may be applied over the fibrereinforced polymeric coating.

Suitably, the decorative coating comprises a polymeric mineral finishsealant.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be more fully understood and put intopractical effect, reference will now be made to preferred embodimentsillustrated in the accompanying drawings in which:—

FIG. 1 shows schematically a perspective view of a structural blocksuitable for use with the invention;

FIG. 2 shows a side elevational view of the block of FIG. 1;

FIG. 3 shows a top plan view of the block of FIGS. 1 and 2;

FIG. 4 shows an end elevational view of the block of FIGS. 1-3;

FIG. 5 shows a cross sectional view through a wall constructed inaccordance with the invention;

FIG. 6 shows a partial perspective view of a finished wall structureaccording to the invention;

FIG. 7 shows one form of lintel structure;

FIG. 8 shows a partial cross-section through a lintel structure;

FIG. 9 shows a truss tie-down to a lintel;

FIG. 10 shows an alternative lintel configuration; and

FIG. 11 shows an alternative block configuration.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIGS. 1-4 there is shown a masonry block suitable for building“dry-stacked” or mortarless wall structures.

Masonry block 1 includes opposed side walls 2, opposed end walls 3 andintermediate webs 4 defining apertures 5 a, 5 b and 5 c extending alongupright axes through block 1.

On the upper face of block 1 there are formed projections 6 adapted tolocate in complementary recesses 7 formed in an adjacent block. Recesses7 are formed in the lower opposite wall portions of apertures 5 a and 5c whereby a channel-like recess 8 extends over the lower face of block 1between the lower portions 2 a, 2 b of opposed side walls 2.

The structure of the block permits quick, accurately aligned stacking ofblocks in a conventional manner wherein the blocks of one course overlapthe end joints between blocks of an underlying course, the end jointsbeing located centrally of central aperture 5 b. Part blocks (not shown)are utilised for wall ends, wall openings and joints between adjacentwalls.

FIG. 5 shows a part cross-sectional view of a wall structure accordingto the invention and illustrates the method of construction according tothe invention.

A first or base course of blocks 10 is arranged in a desiredconfiguration on a floor slab 11 and a quantity of a polymer modifiedcementitious mortar 12 (available under the trade mark “QuickwallAustralia”) is poured into the apertures of the blocks to anchor them tothe slab 11.

The wall is then completed by dry-stacking the blocks of FIGS. 1-4 to adesired height and length.

A fibre reinforced polymeric coating 13 is formed on both wall surfacesby applying a first or base layer of liquid curable polymeric adhesive(also available under the trade mark “Quickwall Australia”) by sprayingor trowelling. The base layer extends over regions 14, 15 of the slab11.

A sheet of alkaline resistant fibreglass mesh of say 100-150 gm m² isthen applied to the wetted surfaces of the slab and the opposite wallsurfaces 16, 17 whereby the fibreglass mesh extends continuously fromslab region 14, over outer wall surface 17, over the top of upper blockcourse 18, down the inner wall surface 16 and finally terminating at theouter edge of slab region 15. The fibre reinforced coating 13 iscompleted by the application of a further or top layer of the sameliquid polymeric adhesive.

Successive sheets of fibreglass are overlapped by about 200 mm wherebythe finished wall structure comprises dry stacked blocks having anintegrally formed high tensile fibre reinforced polymeric skin extendingfrom the floor slab, to which the skin is bonded, up and over the top ofthe wall, effectively encapsulating the wall.

To maximise the structural integrity and weatherproofing of the jointbetween the base course and the reinforced wall skin, a corner bead 13 aof wetted fibreglass rovings, a fibreglass mesh tape or the like ispositioned in the corners between the wall surface and the slab surfaceso that a radiussed joint is formed.

At spaced intervals, rafter or roof truss brackets 19 are anchored tothe wall structure by stuffing a block aperture with, say, newspaper 20and then pouring in a layer 21 of cementitious mortar of the same typeused to bond the base course 10 to slab 11. Bracket 20 is anchored inthe layer 21 and protrudes through the top portion 22 of fibrereinforced layer 13.

FIG. 6 shows a part perspective view of a finished wall construction inaccordance with the invention.

The wall is constructed generally in accordance with the method stepsdescribed in relation to FIG. 5 and as such like features employ likereference numerals where appropriate but where wall openings 25 such asa window, door or the like are concerned additional steps are required.

While the wall is erected very quickly by dry-stacking or the like,there are several ways to form a lintel over a door or window opening.

In one method, a steel angle iron can be used as a lintel support andwhere this is done, the course of blocks forming the lintel beam areinitially tied together and to the steel angle iron with a preliminaryfibreglass reinforced polymer skin 26. Once encapsulated, the wallconstruction can then continue as previously described. When forming thepolymeric fibre reinforced skin 27 on the wall surfaces, the regionsaround the window reveals 28 are also coated with the integrally formedskin 27.

In an alternative lintel construction, a plurality of U-shaped blocksare supported on formwork in an end to end configuration. The centralchannel so formed locates steel reinforcing members and concrete ispoured into the cavity to form a bond beam lintel. The outer surfaces ofthe lintel so formed have a preliminary fibre reinforced polymeric skinformed thereon such that when the final wall structure is coated, thelintel region incorporates a double layer of fibre reinforced polymericmaterial. Depending upon the wind loading for the structure, the lintelmay comprise two or more courses of mortar filled lintel blocks, with orwithout steel reinforcing therein.

The inner and outer wall surfaces are then given a decorative and/orprotective coating of a polymeric mineral finish (once again availableunder the trade mark “Quickwall Australia”). This finish includes agenerally spherical aggregate having a mean diameter of about 2 mmwhereby the aggregate particles act as a guide to permit a trowelledcoating of substantially even 2 mm thickness controlled by the aggregateparticles. This permits the use of less skilled labour in the finalfinishing of the wall surfaces.

FIGS. 7 to 10 illustrates aspects of yet another lintel constructionforming part of the system according to the invention.

In FIG. 7, there is shown a block wall structure 30 with a doorwayaperture 31. Above doorway aperture 31 is a lintel member 32 in the formof a steel frame 33 with void forming cores 34 located therein.

FIG. 8 is an enlarged partial cross-sectional view of a top rail portion33 a of lintel 32 as shown in FIG. 7.

Frame 33 comprises a rolled steel U-section channel 33 a forming a toprail to the rectangular frame and a like member 33 b (shown in FIG. 7)forming a bottom rail. Similar upright channel sections 33 c, 33 c ofslightly narrower width are nested within the outer flanges of top andbottom rails 33 a, 33 b respectively and are secured thereto by asuitable fastening means such as a self-piercing rivet, a self-tappingscrew, welding or the like passing through overlapping channel edgeflanges. A similar upright member 33 e is located intermediate endmembers 33 c, 33 d.

The channel like members 33 a, 33 b, 33 c and 33 d are configured withtheir respective recesses facing inwardly of the frame structure 33 tolocate the foam styrene void forming cores 34 therein.

As shown in FIG. 8, the lintel member 32 comprises a pair of frames 33in side by side juxtaposition with their outer edges flush with therespective opposite faces of adjacent blocks. A top course of blocks 30a extends over the top of lintel member 32.

As with structures previously described with reference to FIG. 5 andFIG. 6, the block wall structure 30 and the lintel member 32 are coatedwith a glass fibre reinforced polymeric skin 35 which extends over thetop of the top course of blocks 30 a and under bottom rail 33 b toencapsulate the blocks 30 a and lintel member 32 where it extends acrossopening 31 whereby the blocks 30 a and the lintel member 32 togetherfunction as a truss member. The outer or exposed surfaces of the wallstructure and lintel member can also have applied thereto a decorativeand/or protective coating 36 of a polymeric mineral finish as previouslydescribed and this, when cured, serves to further reinforce that part ofthe wall structure and the lintel member now functioning as a trussbeam.

FIG. 9 shows a method of attachment of a roof truss 37 to the lintelmember 32 shown in FIG. 8.

Truss 37 is simply secured to the lintel member 32 by fasteners 38extending through angle brackets 39 into the truss 37 and the top railportions 33 a of frames 33 forming the lintel member 32. As the frames33 are subsequently mechanically tied to the wall structure, on whichthe lintel member rests, by the fibre reinforced polymeric skin, bothroof mass and wind loadings are adequately met by this tie-down method.

FIG. 10 shows generally a block wall structure 4 a according to theinvention with a large doorway aperture 41.

To accommodate the roof and wind loading on the lintel structure 42, theframe structures 43 are deeper and a plurality of uprights 44 are spacedalong the top and bottom rail portions 43 a, 43 b between end members 43c, 43 d. Uprights 44 are suitably pairs of rolled steel channel memberssecured in back to back relationship such that foam core blocks 45 aresecured by inwardly facing channel edge flanges extending about theperipheral edges of each core block 45.

Like the composite truss beam structure described with reference toFIGS. 7 and 8, the lintel structure 42, can be engineered to suit thespan by altering the height of the truss beam, the gauge of the steelchannel members etc. Again, like the composite lintel structures ofFIGS. 7 and 8, the lintel structure 42 ultimately relies uponencapsulation by the fibre reinforced polymeric skin in the region whereit spans aperture 41 for its structural integrity.

FIG. 11 shows an alternative configuration of a masonry block 50suitable for erection of dry-stacked or mortarless wall structures.

Like the block of FIGS. 1-4, block 50 includes opposed side walls 51,opposed end walls 52 and intermediate webs 53 defining apertures 54, 55,56 extending along upright axes through block 50.

On the upper face of block 50 there are formed projections 57 extendingpartly transversely of the block and having a shape and configuration toenable the projections 57 to meet in corresponding recesses 57 a on thelower face of a corresponding adjacent block.

On the opposed side wall of block 50 are raised projections 58 forming ascreed guide for a first layer of liquid curable polymeric adhesive.After application of the liquid adhesive by spraying or trowelling, aninitial adhesive layer of even thickness is formed over a wall surfaceby contact of a trowel or screed bar with the raised projections whichact as a thickness guiding mechanism.

For masonry blocks formed by the “Besser” (Trade Mark) process, theprojections 58 are suitably in the form of spaced vertically extendingrib-like formations 59 having any desired spacing and any desiredcross-sectional shape.

As shown, the rib-like formations are regularly spaced and have a smoothundulating or “corrugated” shape with channel-like recesses 60therebetween. Alternatively, the ribs may be formed with a rectangular,part circular or a tapered V-shaped cross-section with a broad spacingtherebetween.

For extruded clay or masonry blocks, the rib-like formations 59 willalso extend parallel to each other and vertically as generally shown.For blocks made in demountable moulds, the pattern of surfaceprojections on the side walls 51 of the blocks may be regular such asspaced circular or rectangular projections or they form an irregularpattern over the side walls 51. All that is required is that sufficientprojections of a predetermined thickness are formed over the side wallsof a block to permit a trowel or screed bar to contact the projectionsas the trowel or screed bar moves over the surface of the block wall toform an adhesive layer of even thickness thereover. This avoids waste inexcessively thick layers of adhesive and otherwise serves to ensure agenerally planar surface in the finished wall structure.

It readily will be apparent to a person skilled in the art that the wallbuilding method according to the invention, and structures builttherefrom, have substantial advantages over prior art masonry blockstructures requiring steel reinforcing in core filled walls.

The wall structures embody all of the structural insulating and firerating qualities of conventional masonry block structure with theadditional advantage of faster erection with less skilled labour andconsequent cost savings.

Further cost savings are obtained by avoiding the need for steelreinforcing in the wall structure and the need for concrete pumping toform the spaced steel reinforced cores as with prior art structures.

The high tensile fibre reinforced polymeric wall skins permits use ofthe structures in cyclone rated geographical regions and, in additionprovide a much more weatherproof and vermin resistant structure thanhitherto possible with conventional masonry finishes.

As an alternative to woven fibreglass reinforcing, non-woven fibreglass,woven or non-woven Kevlar, carbonfibre or synthetic fibrous mats may beused. The fibrous reinforcing may also include chopped fibresdistributed throughout the polymeric coating material.

Throughout this specification and claims which follow, unless thecontext requires otherwise, the word “comprise”, and variations such as“comprises” or “comprising”, will be understood to imply the inclusionof a stated integer or group of integers or steps but not the exclusionof any other integer or group of integers.

1-26. (canceled)
 27. A method for construction of a structural block wall, said method comprising the steps of: erecting on a structural base a wall of mortarless structural blocks wherein a base course of said structural blocks is anchored to said structural base; and, applying to opposite faces of said wall a fibre reinforced polymeric coating wherein said fibre reinforced polymeric coating on at least one of said opposite faces of said wall extends over a portion of said structural base to form a bond between said wall and said structural base.
 28. A method as claimed in claim 27, wherein said base course of structural blocks is anchored to said structural base by a polymeric adhesive compound.
 29. A method as claimed in claim 27, wherein said structural blocks include one or more projections engageable, in use, with complementary one or more recesses in an adjacent structural block.
 30. A method as claimed in claim 29, wherein said structural blocks include projections and complementary recesses on respective opposed faces.
 31. A method as claimed in claim 27, wherein said structural blocks are self-aligning when stacked.
 32. A method as claimed in claim 30, wherein said opposed faces comprise upper and lower faces.
 33. A method as claimed in claim 32, wherein said structural blocks include one or more apertures extending between said upper and lower faces.
 34. A method as claimed in claim 27, wherein said fibre reinforced polymeric coating extends over portions of said structural base on opposite sides of said walls.
 35. A method as claimed in claim 27, wherein said fibre reinforced polymeric coating extends over a top surface of said wall.
 36. A method as claimed in claim 27, wherein mounting brackets are secured to an upper course of structural blocks in said wall to permit, in use, connection of a roof structure to said wall structure.
 37. A method as claimed in claim 36, wherein said mounting brackets are secured to respective structural blocks by a polymeric adhesive compound.
 38. A method as claimed in claim 27, wherein reveal surfaces in wall openings have applied thereto a fibre reinforced polymeric coating formed contiguously with said fibre reinforced polymeric coatings on opposite faces of said wall.
 39. A method as claimed in claim 27, wherein said fibre reinforced polymeric coating includes a layer of fiberglass reinforcing material.
 40. A method as claimed in claim 39, wherein said layer of fiberglass reinforcing material comprises a sheet of woven or non-woven fiberglass.
 41. A method as claimed in claim 40, wherein said fiberglass reinforcing material is an alkaline resistant grade.
 42. A method as claimed in claim 27, wherein said fibre reinforced polymeric coating is formed by applying a base coating of a liquid curable polymeric composition to a surface of said wall, positioning on said base coating a layer of fibre reinforcing material, applying to an exposed surface of said layer of fibre reinforcing material a further coating of a liquid curable polymeric composition and allowing said liquid curable polymeric composition to cure.
 43. A method as claimed in claim 42, wherein said liquid curable polymeric composition is applied to a surface of the wall and/or said exposed surface of said layer of fibre reinforcing material by any suitable means including spraying, trowelling, screeding or squeegee application.
 44. A method as claimed in claim 43, wherein said base coating is applied to a substantially even thickness by means of guide projections extending from opposite normally exposed faces of said structural blocks.
 45. A method as claimed in claim 44, wherein said guide projections comprise spaced substantially parallel ribs serving, in use, to guide a screeding or trowelling device to apply said base coating to a substantially even thickness.
 46. A method as claimed in claim 27, wherein a decorative coating is applied over said fibre reinforced polymeric coating.
 47. A method as claimed in claim 46, wherein said decorative coating comprises a polymeric mineral finish sealant.
 48. A wall structure whenever constructed in accordance with the method of claim
 27. 49. A wall structure comprising: a plurality of mortarless structural blocks stacked to form a wall wherein a base course of said structural blocks is anchored to a structural base; and a fibre reinforced polymeric coating applied to opposite faces of said plurality of stacked mortarless structural blocks wherein said fibre reinforced polymeric coating on at least one of said opposite faces of said wall extends over a portion of said structural base to form a bond between said wall and said structural base.
 50. A wall structure as claimed in claim 49, wherein said base course of structural blocks is anchored to said structural base by a polymeric adhesive compound.
 51. A wall structure as claimed in claim 49, wherein said structural blocks include one or more projections engageable, in use, with complementary one or more recesses in an adjacent structural block.
 52. A wall structure as claimed in claim 51, wherein said structural blocks include projections and complementary recesses on respective opposed faces.
 53. A wall structure as claimed in claim 49, wherein said structural blocks are self-aligning when stacked.
 54. A wall structure as claimed in claim 52, wherein said opposed faces comprise upper and lower faces.
 55. A wall structure as claimed in claim 54, wherein said structural blocks include one or more apertures extending between said upper and lower faces.
 56. A wall structure as claimed in claim 49, wherein said fibre reinforced polymeric coating extends over a top surface of said wall.
 57. A wall structure as claimed in claim 49, wherein mounting brackets are secured to an upper course of structural blocks in said wall to permit, in use, connection of a roof structure to said wall structure.
 58. A wall structure as claimed in claim 49, wherein reveal surfaces of wall openings have applied thereto a fibre reinforced polymeric coating formed contiguously with said fibre reinforced polymeric coatings on opposite faces of said wall.
 59. A wall structure as claimed in claim 49, wherein said fibre reinforced polymeric coating comprises a sheet of woven or non-woven fiberglass.
 60. A wall structure as claimed in claim 49, wherein said structural blocks comprise guide projections extending from opposite normally exposed faces of said structural blocks.
 61. A wall structure as claimed in claim 60, wherein said guide projections comprise spaced substantially parallel ribs.
 62. A wall structure as claimed in claim 49, including a decorative polymeric mineral finish sealant applied over said fibre reinforced polymeric coating. 